An unidentified gunman and others block the road toward the military airport at the Black Sea port of Sevastopol in Crimea, Ukraine, Friday, Feb. 28, 2014. / Ivan Sekretarev, AP

by Oren Dorell, USA TODAY

by Oren Dorell, USA TODAY

The appearance of Russian-speaking armed troops who've seized airports and government buildings in Crimea seems to follow a pattern that has allowed Russia to assert dominance over former Soviet republics that tried to shift toward Europe, an analyst says.

"This is a pattern of Russian policy, divide and conquer, use your leverage through separatist and ethnic disputes" to pressure post-Soviet countries to remain in Russia's orbit, says Damon Wilson, former White House director of European Affairs under then-president George W. Bush.

Russia's message is: "If you go to Europe you lose territory where Russia has its military bases," Wilson said.

Ukraine's autonomous province of Crimea is about 50% Russian speaking, and many though not all say they identify more with Russia than Ukraine.

Russian jets this week have increased patrols along the Ukrainian border, and troops have held military exercises near Ukraine. Giving support to pro-Moscow Crimeans, Leonid Slutsky, who leads the Russian parliament's committee for relations with former Soviet states, visited Crimea on Tuesday and pledged Russian protection if tensions rise, according to U.K. paper The Guardian.

"If the life and health of our compatriots is under threat, we will not stand to one side," Slutsky said.

In Georgia, Russia took military actions in 2008 after making similar warnings to the Georgian governmentthat it must protect pro-Russian peoples there. Like in Crimea, armed men rose up to take control of a breakaway province. In Georgia that action was followed by the arrival of Russian "peacekeeper" troops that pushed out government troops from South Ossetia and Abkhazia and remain there today.

Moldova, like Ukraine and Georgia, declared independence following the dissolution of the Soviet Union in 1991. Soviet troops stationed there shifted allegiance to Russia, and when Russia-speaking separatists in Transnistria demanded to secede, Moscow backed their grievances.The troops have never left despite repeated requests by Moldova's president for their withdrawal from his country's soil.

And when Moldova tried to strengthen ties with Europe, it too encountered obstacles from Russia.

In Ukraine's case, Russian President Vladimir Putin withdrew an economic aid package when protesters demanded Kiev sign a trade pact with the European Union. In Moldova, Russian deputy prime minister Dmitri Rogozin told reporters in September that Moldova may lose part of its country if it went ahead with joining a European trade alliance.

"Moldova's train en route to Europe would lose its wagons in Transnistria," he said. Rogozin also noted Moldova's dependence on Russian natural gas, saying: "The cold season is near. Winter is on its way. We hope that you will not freeze this winter."

Georgia also encountered trouble with Russia when it sought closer ties with Europe and the USA. Russia literally prepared the ground for intervention by repairing railroads years before major fighting broke out in 2008 and Russian troops came in by train.

Wilson, who also served in the State Department under then-president Bill Clinton, said U.S. officials watched as irregular forces who had served in the Russian military joined separatists. Also getting involved were ethnic Cossacks and other volunteers from Russia to reinforce the separatists against the Georgian military.

"We saw it and it was hard for us to imagine the Russians resorting to the use of force, but in the end they did," he said.

Russia also issued Russian passports to Abkhazians and South Ossetians and spoke of protecting ethnic Russian populations in those provinces, and many of the separatist regime leaders were former officials in Russian intelligence and defense ministries, he said.

"There was no pretending about it. The political structures in Abkhazia and South Ossetia were vessels, puppets," Wilson said.

Wilson said he's worried the same strategy is at work in Ukraine, which is an important tourism hub and home to Russia's Black Sea fleet and a shipbuilding industry.

"They're saying if you move toward Europe you're doing so at the expense of losing an important part of your country - the Crimea," he said.

Putin has said Russia has no designs on Ukraine. Some in Moscow say that may be true but it can change.

"Russia has not made any decision on invading Ukraine yet," says Fyodor Lukyanov, editor of the Russia in Global Affairs journal and chairman of the Council on Foreign and Defense Policy. "But there is a demonstration that in case this revolution spreads further into (Eastern Ukraine) regions, then Russia will act."

A bill introduced recently by Russian lawmakers would simplify the process of incorporating new territories into the country. If passed, the bill would allow territories to join Russia through a referendum, sidestepping international treaties.

As it happens, Crimea's parliament has asked for such a referendum to take place in May.